Both Facebook and MySpace are now using Fusion-io Solid State Storage to address the performance challenges of Social Networking. As James Hamilton notes in his Perspectives blog entry Scaling at MySpace social networking are difficult to implement. He calls them “hairballs” because the many-to-many relationships are difficult to partition and scale. Massive daily growth of the hairball makes social networking architectures leading edge.
MySpace and Facebook employ a 3-tier architecture. MySpace infrastructure is comprised of Web tier, Cache Tier and Database tier. MySpace also uses Memcached for in-memory key-value chunks of data paged from SQL server. Solid state storage is ideal for hot data, the cache tier.
Fusion-io’s case study ‘MySpace Uses Fusion Powered I/O to Drive Greener and Better Data Centers‘ highlights that MySpace was able to cut “hardware need by 60%”. It was clarified in the ‘Scaling at MySpace’ comments that the HW reduction was for the cache tier. As summarized in ‘Scaling at MySpace’ the infrastructure consist of:
· 3,000 web servers
· 800 cache servers
· 440 SQL servers
Database tier:
· 440 SQL Server Systems hosting over 1,000 databases
· Each running on an HP ProLiant DL585
o 4 dual core AMD processors
o 64 GB RAM
· Storage tier: 1,100 disks on a distributed SAN (3PAR)
· 1PB of SQL Server hosted data
Applying the 60% reduction factor to the cache tier would indicate that initially was 2000 servers. These servers were provisioned with 10-12 15K rpm SAS drives and a RAID storage controller. After the upgrade the cache tier was provisioned at 800 cache servers with two 320GB ioDrives each for a total of 1600 ioDrives. In summary it appears MySpace was able to decommission roughly 1,200 cache servers, 2,000 SAS RAID controllers and 20,000 SAS HDDs by the deployment of Fusion-io ioDrives in this random hot data application.
While energy footprint was not the sole reason for deploying solid state storage in the cache tier it is noteworthy that the overall power reduction was most likely near 700 kWh.
· 1,200 cache Servers @ 250 watts each = 300 kWh
· 2,000 PCIe SAS RAID controllers @ 25 watts each = 50 kWh
· 20,000 15K rpm SAS HDDs @ 18 watts each = 360 kWh
Add back in 1,600 Fusion-io ioDrives and factor in a PUE of 1.6, this would be a reduction of 1,070 kWh. At $0.10 kWh a savings of $940K/yr would be realized. This kind of real-world data is valuable when considering the deployment of new technology. Realistic ROIs are can now be determined for right-sizing of capacity and performance. In addition there are some significant ramifications for existing technologies such as traditional PCIe RAID when used in hot data or random workload applications.